TABLE OF CONTENTS The highest measurement data rates are provided by crate and modular measurement systems with parallel interface. In crate systems, instruments are arranged in crates, also referred to as chassis or mainframes, containing measurement system functional modules, as shown in Figure 9.1. Crates are mounted in racks, a short distance (approximately 30 to 50 cm) from one another, which favors low transmission line capacity and affords high transfer rates. Two types of crate measurement systems are in widespread use: Computer Aided Measurement And Control (CAMAC) systems, which are rather out of date now, and VXI systems (VME extensions for Instrumentation), the former's junior by 20 years [1, 2]. Although VXI systems have been supplanting their CAMAC counterparts for about 10 years, CAMAC crates, functional blocks, and mechanical constructions are still manufactured and used.
VXI, another standard of crate measurement system using parallel interface, is a specialist system composed of modules that are designed exclusively for operation in this type of system. Modules are arranged in a chassis and are mounted in racks. Due to these features, the VXI interface system allows very high rates (up to 40 MBps) of measurement data transfer. VXI measurement systems are used in military technology and nuclear engineering, fields in which data processing rate is crucial for security.
A new standard of measurement system with parallel interface is PXI, a modular system based on PCI (the...
